"Six months is such a long time for a little girl to be separated from her family," Kate McCann said in a statement released Saturday. "We believe that our Madeleine is out there somewhere and retain hope that we can be reunited.

"Madeleine is a beautiful little person who deserves a loving and happy life. To ensure this, there is no doubt that the best place for her to be is with her family. We know somebody somewhere can make this happen."

The disappearance of the British child May 3 made headlines around the world. Her parents have said she disappeared from their hotel room at a resort in Praia da Luz, Portugal, while they dined in a nearby restaurant.

Kate McCann and her husband Gerry embarked on a high-profile campaign to highlight their daughter's plight, traveling throughout Europe and Africa. A Web site, Find Madeleine, has raised more than a million pounds ($2 million) toward locating the girl, who went missing just a few days before her 4th birthday.

The parents, who are devout Catholics, met with the Pope and enlisted the support of celebrities and sports stars including soccer player David Beckham and author J.K. Rowling.

The McCanns were expected to mark the anniversary Saturday at a prayer service in their hometown, according to a blog entry posted by Gerry McCann earlier this week.

In spite of a huge media focus on the disappearance and a number of suspected sightings in Europe and North Africa, no arrests have been made in connection with the case. However, massive media interest has resulted in a tidal wave of speculation in the British and Portuguese press.

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Media coverage of the case, which has rarely left the front pages of British newspapers in the last six months, grew further in September when the McCanns, both 39, were named as suspects by Portuguese investigators. Both have strongly denied any involvement in their daughter's disappearance.

On Thursday, Gerry McCann returned to his job as a cardiologist, saying he had done everything he could personally do to find his daughter and that he now will be relying on the search campaign to continue the effort.

"We've got an infrastructure and support system behind us now, and to be honest, unless Madeleine's found, we're not expecting any significant developments in the near future," he told reporters.

Although Kate McCann is also a doctor, she does not plan to return to work and will focus instead on finding Madeleine and raising the couple's two other children, family spokesman Clarence Mitchell has said.

Mark Williams-Thomas, a former detective and child protection expert, said the two most likely scenarios are that Madeleine was killed by accident and her death was covered up or that she was abducted.

"If we work on the basis that she was abducted by a pedophile, a predatory pedophile, the likelihood is that she would have been killed between 48 hours and 72 hours after the pedophile had gotten their self-gratification," he told CNN.E-mail to a friend